What is the recommended management for a patient with a port showing resistance to flushing and medication administration, despite prior replacement and reaccess?

From the Guidelines

For a port showing resistance to flushing and medication administration despite prior replacement and reaccess, the recommended management is prompt consultation with interventional radiology or vascular access specialists for definitive evaluation. The resistance likely indicates either partial thrombosis, catheter malposition, pinch-off syndrome, or fibrin sheath formation. While awaiting specialist assessment, avoid forceful flushing which could dislodge a clot or damage the catheter. If thrombosis is suspected, tissue plasminogen activator (tPA) instillation may be ordered (typically 2mg in 2mL instilled into the port for 30-120 minutes) to dissolve the clot. For fibrin sheath formation, the specialist may perform over-the-wire exchange of the catheter. Radiographic studies including chest X-ray or contrast-enhanced port study (venogram) will likely be necessary to identify the exact cause of obstruction.

• Key considerations in managing port dysfunction include:
  • Avoiding the use of heparin for locking long-term CVADs, as sodium chloride 0.9% is recommended instead due to its lower risk of biofilm formation and CVAD occlusion 1
  • Ensuring proper care and maintenance of the port, including regular flushing and locking with saline solution, to prevent complications such as infection and thrombosis 1
  • Minimizing contamination risk by scrubbing the access port with an appropriate antiseptic and accessing the port only with sterile devices 1 Port dysfunction requires prompt attention as it can lead to medication extravasation, treatment delays, and increased infection risk. Never forcefully flush a resistant port as this could cause catheter rupture or embolization of debris into the circulation.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Cathflo® Activase® (Alteplase) is for instillation into the dysfunctional catheter at a concentration of 1 mg/mL If catheter function is not restored at 120 minutes after 1 dose of Cathflo Activase, a second dose may be instilled

The patient's port is showing resistance to flushing and medication administration, despite prior replacement and reaccess. Alteplase (Cathflo Activase) can be considered to restore catheter function.

• The recommended dose is 2 mg in 2 mL for patients weighing ≥30 kg.
• If catheter function is not restored after one dose, a second dose of equal amount may be instilled. 2 2

From the Research

Patient Management

The patient has a port showing resistance to flushing and medication administration, despite prior replacement and reaccess. The patient's history includes lymphedema, recurrent cellulitis, DM, PAD, COPD, hypothyroidism, and chronic pain syndrome.

Heparin Use

• The use of heparin in patients with venous thrombosis and pulmonary embolism has been established as an effective treatment 3.
• However, heparin-induced thrombocytopenia is a potential risk, and alternative anticoagulants may be necessary in such cases 4.
• Intermittent flushing with heparin has been shown to be effective in maintaining peripheral intravenous catheters, with a lower risk of occlusion and phlebitis compared to saline flushes 5.
• Heparin flushing has also been used to prevent port system-associated thromboses in advanced oncology patients, with a concentration of 500-1000 IU/mL being effective 6.

Recommendations

• Considering the patient's history and current resistance to flushing and medication administration, heparin flushing may be a viable option to maintain patency of the port.
• However, the patient's bleeding risk and potential for heparin-induced thrombocytopenia should be carefully evaluated before initiating heparin therapy.
• The use of low-molecular-weight heparin (LMWH) may be considered as an alternative to unfractionated heparin, as it has been shown to be effective in preventing venous thromboembolism in high-risk patients 7.